Telephone system.



' PATLNTLD APR. 9, 1907.

L. P. MLLER.

TELEPHONE SYSTEM.

APPLICATION FILED AUG. 7, 1905A.

INV-ENTOR WITN ESSES ATTORNEY EATENTED AEE. 9, 1907. I

'NOA 849,850.

L. E. MLLER. TELEPHONE SYSTEM. l APPLICATION FILED AUG. 7, 1905.

2 SHEETS-SHEET 2.

Num bb ATTORNEY.

Ifi

LEOPOLD F. MLLER, OF PASSARE, NEW JERSEY.

TELEPHONE sYs'TEIvn Specification of Letters Patent.

Patented April 9, 1907.

Application nea August 7,1905. sean No. 272,971.

To alt whom it may concern".-

Beit known that I, LEOPOLD F. MLLER, a subject of the Emperor of Germany, residing at Passaic, in the county of Passaic and State of New Jersey, have invented certain new and useful Improvements in Telephone Systems; and I do hereby declare the following to be a full, clear, and exact description of thev invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters of lreference marked thereon, which-,form a part of this specification.

This invention relates to that class of electric telephonie systems in which a number of stations are employed and by lwhich a calling party at either of said stations can make a connection with any one of the other stations without the intervention or aid of a central office.

The objects of the present improvements are to prevent short-circuiting Vof currents, and consequently prevent interference with a proper communication between stations, especially where said stations are distant from one another, to avoid the production and use of induced currents'and the disadvantages arising therefrom, and to secure other advantages and results, some of which ma be hereinafter referred to in connection wit the description of the working parts. Y The invention consists in the improved telephone sy tem and in the arrangements and combinaltions of parts of the same, all substantiallyas will be hereinafter set forth and finally embraced in the clauses of the claim.

Referring toithe accompanying drawings, in which like letters of reference indicate corresponding parts in each of the several iigures, Figure 1 is ak diagrammatic view of my improved system; Fig. 2 is a front view of a ocal-station box and contents, showing certain off-the improvements in detail, the

lfront board being removed; and Fig. 3 is a section of the same at line p In said drawings, 1, 2, 3, and 4 represent four stations, the number in practice being greater or less, as circumstances may lrender desirable. These are usually constructed and the parts therein are arranged electrically connected and operated in uniform manner.

In station 1 the bell-circuit is shown closed ceiverissuspendedfromitshook, or, similarly, 1 1o to occasion the ringing of the bell B, While in station 4 thetransmitter-hook is shown raised into closed contact with the terminals of the transmitter and receiver wires ready for talking. 5, 6, 7, 8, and 9 are constant and unvarying line-wires on which the stations are disposed, and 10, 11 12, andv 13 are line-wires which vary in number in correspondence with thenumber of stations thereon and with which the several stations 1 2 3 4 are connected, the battery 14 being disposed on'the positive and negative wires 6`and 5 and the batteries 15 and 16 being'stationed onthe wires 7, 8, and 9. The wires 7 and 9 are negative wires and coperate'with the one ositive wire 8. In lconnection with the inewires 5, 6, 7, 8, and 9 are at each station branch wires 17 18 19 20 21 22', extending to and having terminals at the switches 23 24 of the bell B and the transmitter T and receiver R.

For convenienceof speciiic reference the terminals of the wires referred to and to be referred to engaged by the switches 23 24 are marked, respectively, 25-26 27 28 29 31 32.

The receiver-hook H of each station is in permanent connection with a local wire 33,

aving thereon a series of normally open hand-operable contacts 34,'adapted to connect with springs or other terminals 35 on branches 37 38 39 of the line-wires 10 11 12 13. Said splrings are operated by push-buttons or other and-operated devices. Said hook I-I when `supporting the receiver R is in normal contact with a terminal 40 of another Wire 41, eXtendin to the bell-switch terminal26, but when re ieved of the'weight of the receiver said hook, actuated automatically by a spring or other usual means, (not shown,) rises into closed Contact with the terminal 42,

-in connection, as usual, with transmitter T and receiver R and with the contact 43 `of a spring 44 on a branch wire 36, connecting at station 1 with the line-wire 10, at station 2` with the line-wire 11, at station 3 with the line-wire 12, and at station 4 with the linewire 13, and should 'the stations be multiplied to an ex-tent. greater than shown then these line-wires are accordingly multiplied.

In" connection normally with the spring 44 is a terminal 45 of a wire 46, leading to a terminal contact 25, adapted to be lengaged by the bell-switch 23. Under normal conditions, or when the reroo when a station is notin immediate use, the parts are as illustrated by stations. 2 and 3, the circuit connections of the stations being open.

Upon pushing against the button or handoperable device 351 of astation-such, for example, as shown in Fig. 3-to close the contact spring or terminal 35 against the contactterminal 34 the four contact-switches at that the vparty called is ready to talk.

station are automatically and together moved from their contact with the terminals 25 27 29 31, as will readily be understood upon reference to Figs. 2 and 3, into engagement with the terminals 26, 28, 30, and 32, thus establishing a closed bell-circuit Abetween the calling and called station, so that the bells or callingsignals are caused to ring continuously until the receiver of the desired distant station is removed from the hook, when both bells stop thence to the other arm of said switch to local Wire 41, to terminal 40, in normal contact with the hook H, thence through said hook and local-wire 33 to the closed terminals or contacts `34e 35C to the local branch Wire 39 and line-wire 13 to station 4, in connection with said wire 13, where it flows through wire 36 to spring 44, terminal contact 45, normally in connection therewith, local wire 46, armswitch 23, bell B, second arm of the bellswitch to branch-Wire 17, line-wire 9, to the negative pole of the battery 16. Thus the be ls of stations 1 and 4 continue ringing until the circuit thus established xis openedvby .the raisingl of thereceiver-hook, and by reconcerted plan the hook 'raised is at the ca led station, so that the caller is notified of the presence of the person called by the cessation of the ringing at his own station, as above indicated.

The removal of the receiver R from the hook H at the called station permits the automatic raising of said hook in any ordinary manner, so that the bells cease ringing and the talking-circuit is automatically closed at said called station. To this end the hook enters into closed contact with the terminals 42 and 43, as shown at station 4. To complete the talking-circuit, the receiver `at the calling-station is also removed from the hook. Tracing the course of the current from the negative pole of battery 14, said current passes through wire 5 and branch wire 20 at station 1 to or from one arm of the trans-` -mitter and receiver switch 24, through transminals 34 35, andwire 39'of stat-ion 1, and through line-wire 13, connecting With station 4, and finally through local branch wire 36, spring 44, terminal 43, hook H,terminal 42, receiver R, arm of switch 24, branch 21, linew'ire 6, and the positive end of battery 14.

Beginning with the negative pole of the battery 15,'the path of the electrical current is traced over wire 7, branch wire 22, arm of the switch 24, to .the receiver R, and terminal 42, hook H, Wires 33, terminals 34 35, and branch wire 36, station 4, spring 44, hook H, transmitter T, one arm of switch 24, branch Wire 19 to the positive pole ofthe battery 15. Thus the back and forth transmission of sound-vibrations are transmitted from the ltransmitter of one station to the receiver of the other station, and vice versa, as will be readily understood. s

By replacing the receivers on their hooks the contacts o? 34c and 350, for example, are interrupted automaticallyand by means of a spring (not shown) on the shaft 231, bearing on the oscillating terminals or contacts of the switch or switches 23 24, said terminals are brought back to their normal engagement with the terminals 25 27 29 31, as will be understood upon reference to Figs. 2 and 3.

The operation of each call-box is the same, and the hook-arm H, while shown in Fig. 2 raised, is much lower when the receiver is in place, and in that case the pin 50 on the hookarm is below the roller 49 instead of above it. Thuswhen the upper button 351 is pushed in the .terminal 34b is thrown around on its axis 57 to allow the end of the spring 35b to engage it. This action also causes the bar to be operated to ythrow the switch 24 over in contact with the terminal 32. The locked engagement between the terminal 34D and the spring 35b is insured by the springs 56. Now when the receiver is taken oilthe hook and it rides up the pin 50 will ride over the roller 49 by reason of its being on the end of an arm 47, pivoted at 46. When the operator is through talking and hangs the receiver back on the hook, the pin 5() engages the roller 49' and the arm 47 abuts on the arm 51 and both arms are oscillated on th'e pivot 52. On this pivot the arm 51 has an enlarged flattened portion 53, that fits in between the leaves 54, that are engaged on the ivots 55. This tilting of the flattened portion spreads one end of these plates 54 and necessarily draws toward one another the other ends, and these carrying with them IOO IIO

the terminals 348L and 34h, swinging on their lpivotal pins 57, allow the springs 35a and 35b mitter T, and terminal 42, noW in contact l sition by means of the coiled spring 232, 65 With the hook H, next through wire 33. teri which is wound around the ax1s 231.

Having thus described the invention, what I claim as new is l 1. A telephone system comprising a pair of line-wires connected to a battery, a pair of batteries having a positive wire 1n common, a pair of negative wires connected to the pair of batteries, a series oi stations, each station containing a signal, a transmitter and a receiver, the signal being connected to one of the last-mentioned negative wires, the transmitter to the common positive wire, and the receiver to one of the line-wires anda seriesb of line-wires connecting the stations.

2. A telephone system-comprising a pair of line-wires connected to a battery, a pair of batteries having a ositive wire in common, a pair of negative wires connected to the pair of batteries, a series of stations, each station containing a si nal, a transmitter and a re-4 ceiver, a switc to connect the signal with one of the last-mentioned negative wires, or the commonpositive wire, a switch to connect the transmitter with the common positive wire or one of the line-wires, and a switch to connect the receiver with one of the linewires or the othernegative of the wires of the pair of batteries and a series of lline-wires o batteries, a series of stations, each station containing asigna1,a transmitter anda receiver, a switch to connect the signal with one of the last-mentioned negative wlres, or the common positive wire, a switch to connect the transmitter with the common positive wire or one of the line-wires, a switch to connect the receiver with one of the line-wires or the other negative of the Wires of the pair of batteries, and means for operating the switches in unison anda series of line-wiresA connecting the stations.

n testimony that I claim the foregoing I have hereunto set my hand this 31st day of July! 1905.

y LEoPoLD F. MLLER.

Witnesses Y CHARLES H. PELL, RUSSELL M. EVERETT. 

